Yes, anything could be converted as a gambling because betting on anything is possible (at least in teasing manner).

We do bet on "who will finish off the pizza first" or like "who will climb the staircase first", even these are done for no money, the winner may ask for a treat later on. I do really enjoy on this as winning is possible and feasible for me regardless of how new a task will be.

Gamble for fun and if chances are on your favor then make some benefits which fits more exactly here. Moreover, it cannot be illegal as per any culture nor jurisdiction too. Just make fun with your family or friend or colleagues or neighbors by making anything as a gambling.